Why Internal Coating Is Necessary For Oil And Gas Pipeline?

Why internal coating is necessary for oil and gas pipeline?

 External Coating and Internal Coating of pipeline.jpg

Corrosion is the primary factor affecting the longevity and reliability of offshore and onshore buried pipelines throughout the world. Epoxy coatings offer excellent resistance to high temperatures, chemicals and corrosion.Oil and gas protective coatings can be divided into two separate categories, each with its own unique and demanding requirements:External Coatings and Internal Coatings.When referred to anti-corrosion, people naturally think of the external anti-corrosion, such as three layer Polyethylene Systems(3LPE) and three polypropylene layer(3LPP), but the internal pipeline coating is as the same important as external coating for protection of the pipeline.


Oil and gas fluids contain solid particulates such as sodium chloride, potassium chloride, other salts, carbonates, sulfates, partially polymerized oils, including waxes silicas as well as dirt .Some of these particulates dissolve in the fluid while some remain in suspension. Traveling through pipelines at speeds approaching 200 mph, these particulates become aggressively corrosive projectiles. Coatings designed for internal pipeline application must be engineered to withstand the high impact created by these fast moving particulates.

An epoxy resin lining effectively reduces the friction resistance between the fluid and the pipe. This internal coating is applied in liquid or powder form on steel pipes used for oil, gas, water, industrial and corrosive fluids, etc. It is especially used in production and conduction pipelines, and in oilfield drilling tools (drilling pipes, sucker rods, packers, pumps, tubing, casing, etc.) where corrosion problems and paraffin deposits are likely, as well as in special connections for protecting welded joints.

Now the most widely used internal anti-corrosion options is in the following:

●Liquid epoxy coating

Liquid epoxy coating provide a thermoset end-product with a unique combination of properties.

WORLD IRON&STEEL internal pipeline is compliance with all major international standards such as API RP 5L2, ISO 15741, BS/EN 10301.

●Internal Fusion Bonded Epoxy (FBE)

Fusion Bonded Epoxy coating has excellent chemical resistance and better dimensional stability. however,the cost of Material and labor is expensive,Pipe and coating must be heated to 250°F when operating.


World iron &steel supply 3LPE and 3LPP coated pipeline for transportation of oil,gas,water and other fluid.Our coating steel pipe is produced by a process of coating with a primer and polyethylene or polypropylene layer for small and medium diameter line pipe by extruded method and by spiral wrapping methods for large diameter line pipe.Email to info@worldironsteel.om to learn more!